Source code for airflow.contrib.operators.vertica_to_mysql

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import MySQLdb

from airflow.contrib.hooks.vertica_hook import VerticaHook
from airflow.hooks.mysql_hook import MySqlHook
from airflow.models import BaseOperator
from airflow.utils.decorators import apply_defaults

from contextlib import closing

import unicodecsv as csv
from tempfile import NamedTemporaryFile

[docs]class VerticaToMySqlTransfer(BaseOperator): """ Moves data from Vertica to MySQL. :param sql: SQL query to execute against the Vertica database. (templated) :type sql: str :param vertica_conn_id: source Vertica connection :type vertica_conn_id: str :param mysql_table: target MySQL table, use dot notation to target a specific database. (templated) :type mysql_table: str :param mysql_conn_id: source mysql connection :type mysql_conn_id: str :param mysql_preoperator: sql statement to run against MySQL prior to import, typically use to truncate of delete in place of the data coming in, allowing the task to be idempotent (running the task twice won't double load data). (templated) :type mysql_preoperator: str :param mysql_postoperator: sql statement to run against MySQL after the import, typically used to move data from staging to production and issue cleanup commands. (templated) :type mysql_postoperator: str :param bulk_load: flag to use bulk_load option. This loads MySQL directly from a tab-delimited text file using the LOAD DATA LOCAL INFILE command. This option requires an extra connection parameter for the destination MySQL connection: {'local_infile': true}. :type bulk_load: bool """
[docs] template_fields = ('sql', 'mysql_table', 'mysql_preoperator', 'mysql_postoperator')
[docs] template_ext = ('.sql',)
[docs] ui_color = '#a0e08c'
@apply_defaults def __init__( self, sql, mysql_table, vertica_conn_id='vertica_default', mysql_conn_id='mysql_default', mysql_preoperator=None, mysql_postoperator=None, bulk_load=False, *args, **kwargs): super(VerticaToMySqlTransfer, self).__init__(*args, **kwargs) self.sql = sql self.mysql_table = mysql_table self.mysql_conn_id = mysql_conn_id self.mysql_preoperator = mysql_preoperator self.mysql_postoperator = mysql_postoperator self.vertica_conn_id = vertica_conn_id self.bulk_load = bulk_load
[docs] def execute(self, context): vertica = VerticaHook(vertica_conn_id=self.vertica_conn_id) mysql = MySqlHook(mysql_conn_id=self.mysql_conn_id) tmpfile = None result = None selected_columns = [] count = 0 with closing(vertica.get_conn()) as conn: with closing(conn.cursor()) as cursor: cursor.execute(self.sql) selected_columns = [ for d in cursor.description] if self.bulk_load: tmpfile = NamedTemporaryFile("w") "Selecting rows from Vertica to local file %s...", csv_writer = csv.writer(tmpfile, delimiter='\t', encoding='utf-8') for row in cursor.iterate(): csv_writer.writerow(row) count += 1 tmpfile.flush() else:"Selecting rows from Vertica...") result = cursor.fetchall() count = len(result)"Selected rows from Vertica %s", count) if self.mysql_preoperator:"Running MySQL preoperator...") try: if self.bulk_load:"Bulk inserting rows into MySQL...") with closing(mysql.get_conn()) as conn: with closing(conn.cursor()) as cursor: cursor.execute("LOAD DATA LOCAL INFILE '%s' INTO " "TABLE %s LINES TERMINATED BY '\r\n' (%s)" % (, self.mysql_table, ", ".join(selected_columns))) conn.commit() tmpfile.close() else:"Inserting rows into MySQL...") mysql.insert_rows(table=self.mysql_table, rows=result, target_fields=selected_columns)"Inserted rows into MySQL %s", count) except (MySQLdb.Error, MySQLdb.Warning):"Inserted rows into MySQL 0") raise if self.mysql_postoperator:"Running MySQL postoperator...")"Done")